Files & Programs
I have decided to add this page to my site. It will be just for things I have written or other's files I have found interesting. In many cases, they will be zipped. So when you click on the file to down load it, you will be asked whether or not to open it in place or save it to disk. By all means, save it to your disk. Then put it into some folder of your choice and unzip it!
Download Spread Sheet for Aerodynamics vs Speed vs Hp
One of the racers who plays in the Silver State and other local open road races has gathered some of the data found on this site and made it into a tool that fits his racing needs. He agreed to let me publish his arrangement of the data in his excel format. I present this to you readers and racers to use freely if it also suits your needs. The text of exchanged messages is included also because there is some explanation of how he used it to modify rolling resistance factors. Enjoy! Courtesy of Bob Holman.
Tell you what. Exercise the spreadsheet first. By incorporating it into your web site you are effectively endorsing it, and I may have made some mathematical misinterpretations. Notwithstanding I can't take credit for it anyway, its just a spreadsheet. The formulas and insert values are yours just rearranged in a different format.
To watch the values change plug different numbers into the yellow cells. I believe the total RWHP results are reasonably accurate between 140 and 230 mph but they probably fall apart on either side.
The spread sheet include a number of car type worksheets. The SVT, Camaro and 88GT are real cars with RWHP @ SL actual dyno'd values. The speeds where these cars hit the drag wall, i.e. 210, 228 and 170 respectively, again are actual values at 5500 ft. The available RWHP at altitude for each of these cars has been made to converge to there drag wall speeds by adjusting the fs factor. The other two cars are what-ifs.
I usually set up a separate worksheet for each car being evaluated so I can compare results when making theoretical engine or aero changes. Its already helped me decide to stay with my 8GT, make some air dam changes (to lower CD), continue to run a 302 small block and consider going with a power adder (I want the car to be able to run past 185 mph).
Its been fun to develop. Thanks again
Bob, if you want to share your spreadsheet, send it to me and I will put it on the web sites with proper attribution to you. Information is worthless unless it is shared! If you agree, write up a small lurb about how to use the spreadsheet and I will put that puppy on the site!
Thanks for the kind words!
mayf, out in Pahrump
and prior to the above...
> I have really been enjoying your website and wanted to thank you, particularly for the analysis and CD pages
> I periodically open road race in the Silver State Classic Challenge and the > MKM series of races in northern Nevada and wanted to know the speed > capabilities of my car (88 Mustang GT) ith different RWHP possibilities and > aero modifications. There is information but its spread all over the place.
> I was lucky enough to find your above two web addresses.
> I combined the formulas into a composite spread sheet, used your CD and frontal area data and adjusted the rolling resistance Speed Coefficient fs to make the spreadsheet converge for speeds between 140 and 230 mph. The spreadsheet accurately calculates RWHP at a given altitude and ambient temp > for cars with a known CD and frontal area. The fs factor was derived from a > curve fit of the 88 GT running 150 mph and a 98 Mustang SVT running at 210 > mph (on a flat level highway) and checked against a 96 Camaro running at 228 mph. Works great! Perfect to run through a number of what-if scenarios using different auto make and model body styles.
> Thanks for your hard work.
Download Car Test
I have added the older version of car test program to the web site for download. This is a zipped file and is 369Kb in size. It is a DOS program, not windows! When you click on the title a screen should open up asking you what to do with the file because it is zipped. You tell it where you want to save it. When done, unzip and use it. It is really easy. So, enjoy!
Download Top Speed & Horsepower
This file is an Excel spreadsheet that I wrote to help out the Cobra crowd. They are just like the rest of us in wanting to know how fast their car will go, or how much horsepower it will take to go some certain speed. I wrote it because it appealed to me. It has tire rolling resistance built in and it uses real air density, not that confounded density altitude! You have to find your own Cd, frontal area, etc. But when you have put in the data, it can either figure out what speed a given flywheel hp will achieve, or knowing how fast, how much power it takes. I used Office 97's version of Excel . And for the first part, known horsepower, you need to use Goal Seek.
Charge Air Cooling Thoughts and Analyses
This file is an Excel spreadsheet that I wrote to help out you figuree the best way to cool you chage air. There are four scenarios: a basic input section, a constants section, and calculated data section. Really simple to use. I used Office 97's version of Excel.